The Clinical Effect of Acupuncture in the Treatment of Obstructive Sleep Apnea: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Table 1

Characteristics of included studies.

Study	Country	Study design	Population	Age (mean or range)	EC approval
Freire et al., 2007 [22]	Brazil	RCT	MA: 12; SA: 12; Control: 12	MA: 54.0 (51.0–63.0); SA: 53.0 (49.0–63.0); Control: 57.0 (50.0–64.0)	Yes
Chen et al. 2008 [23]	China	RCT	MA: 44; nCPAP: 22	MA: 55.44 ± 11.04; nCPAP: 56.73 ± 10.21	Not reported
Freire et al., 2010 [24]	Brazil	RCT	MA: 10; 2 Hz EA: 10; 10 Hz EA: 10; Control: 10	MA: 57.7 (44.0–68.0); 2 Hz EA: 52.9 (33.0–69.0); 10 Hz EA: 54.8 (35.0–71.0); Control: 54.3 (35.0–69.0)	Yes
Zhang, 2014 [25]	China	RCT	2 Hz EA: 30; Control: 30	2 Hz EA: 69.45 ± 6.78; Control: 70.01 ± 5.94	Not reported
Zhang et al. 2014 [26]	China	RCT	MA: 45; nCPAP: 45	MA: 48.45 ± 9.76; nCPAP: 51.96 ± 9.87	Not reported
Song et al., 2015 [27]	China	RCT	2 Hz EA + nCPAP: 36; nCPAP: 34	2 Hz EA + nCPAP: 53.17 ± 10.20; nCPAP: 52.71 ± 11.26	Yes

Note. RCT: randomized controlled trial; MA: manual acupuncture; SA: sham acupuncture; EA: electroacupuncture; nCPAP: nasal continuous positive airway pressure; EC: ethical committee.